1. Field of the Invention
The present invention relates to a vehicle-equipment control apparatus, and particularly to a vehicle-equipment control apparatus of a type wherein when an arbitrary control instruction unit of a plurality of types of control instruction units having different switch functions is fit to a switch mounting portion of a control device, the type of a switch function of the fit control instruction unit can be automatically determined.
2. Description of the Related Art
A plurality of manually-operated switches for controlling and adjusting air conditioning in a vehicle room are conventionally placed on a panel surface of a vehicle instrument panel. Any of the plurality of switches is selectively operated to thereby switch the air conditioning in the vehicle room to a cooled or heated state or the like or increase and decrease the temperature at cooling or heating.
However, according to user demands, ones wherein switch built-in portions allowing the mounting of a plurality of optional manually-operated switches as an alternative to the plurality of manually-operated switches for controlling and adjusting the air conditioning in the vehicle room are provided on a panel of an instrument panel, i.e., switch devices having unit mounting portions to which a plurality of types of control instruction units are respectively attachable and wherein one or a plurality of control instruction units different in type for achieving functions desired by a user, e.g., functions such as a headlight optical-axis adjustment, fog-lamp lighting control, the opening of a trunk, etc. are mounted to the unit mounting portions, and switching between the mounted control instruction units is performed to thereby make it possible to cope with user's options, have been recently proposed.
In this case, the proposed switch devices are those wherein any type of control instruction units are attachable to the unit mounting portions and even if any type of control instruction units are fit to the unit mounting portions, the functions of the fit control instruction units can be achieved by performing switching between the fit control instruction units under the processing of switching signals outputted from the control instruction units by a controller (CPU) of a control apparatus or device.
Of such types of known switch devices, a vehicle-equipment control apparatus provided with the function of automatically determining, when control instruction units are respectively mounted to unit mounting portions, the mounted control instruction units, has been also proposed.
The proposed switch device comprises a plurality of types of control instruction units, a control device for selectively mounting these control instruction units to unit mounting portions, and at least one control circuit unit incorporated in the control device. Recognition signal generating means for generating recognition signals peculiar to the control instruction units is provided on the control instruction units side. Further, a switch determination circuit for receiving each recognition signal therein and generating a signal for driving a predetermined load is provided on the control circuit unit side. In this case, the recognition signal generating means has internal interconnections or wires different from one another every control instruction units and outputs different recognition signals (switch signals) when the switches of the control instruction units are operated (turned on). Further, the switch determination circuit has a plurality of logical circuits, a plurality of input terminals and a plurality of output terminals. When a recognition signal (switch signal) is supplied to any of the plurality of input terminals from the corresponding mounted control instruction unit, the switch determination circuit generates a driving signal supplied to a load corresponding to the function of each control instruction unit fit to any output terminal according to the signal-supplied input terminal and the polarity of the recognition signal (switch signal) or the like.
According to the proposed switch device, when a desired type of control instruction unit is attached to a unit mounting portion of the control circuit unit and the switch of the control instruction unit is turned on, a recognition signal peculiar to the function of the control instruction unit is generated from the control instruction unit and supplied to the switch determination circuit of the control circuit unit, whereby the type of the attached control instruction unit is determined based on the recognition signal received by the switch determination circuit. Thus, the switch device can automatically determine the control instruction units having various functions by simply replacing the control instruction units attached to the unit mounting portions with others and is capable of executing operations corresponding to the functions of the control instruction units.
While the above-mentioned switch device can automatically determine the control instruction units having the various functions by simply mounting the control instruction units to the unit mounting portions of the control circuit unit and execute the operations corresponding to the functions of the control instruction units, the different internal wires including the switches must be provided on the control instruction units sides every types of control instruction units to determine the functions of the control instruction units, and the switch determination circuit having the plurality of logical circuits, the plurality of input terminals and the plurality of output terminals must be provided on the control circuit unit side.
From the viewpoint of these, the above-mentioned switch device has a problem in that the means for determining the control instruction units is complex and the control circuit unit spontaneously increases in manufacturing cost and a limitation is spontaneously imposed on the combination of the logical circuits in the switch determination circuit, whereby the control instruction units cannot be increased in kind.
In order to cope with such a problem, a vehicle-equipment control apparatus capable of determining the functions of control instruction units provided with switches, variable resistors, etc. with a very simple configuration without increasing the manufacturing cost has been proposed by the same applicant as one for the present invention. This has already been filed as U.S. Pat. No. 5,990,571 and EP 97110430.2.
The vehicle-equipment control apparatus described in U.S. Pat. No. 5,990,571 and EP 97110430.2 is one wherein resistive elements are principally used within the control instruction units to fractionally divide analog voltages inputted to the control instruction units, and the resultant divided outputs of analog voltages are analog-to-digital converted into digital form, after which they are processed by a CPU (controller).
Thus, the vehicle-equipment control apparatus described in U.S. patent Ser. No. 08/880,119 and EP 97110430.2 is accompanied by a problem to be newly solved that a processing speed cannot be quite made fast because time is spent in analog-to-digital conversion and it is difficult to obtain high reliability due to noise overlapped at an analog voltage circuit portion, for example.